Conversion of vernonia galamensis oil to pyridinylvernolamides and their antimicrobial activities

Abstract

Vernonia oil obtained by Soxhlet extraction from the seeds of Vernonia galamensis ssp. nairobensis was reacted with 2-aminopyridine, 2-(aminomethyl)pyridine and 2-(aminoethyl)pyridine using a 1:3 mole ratio of vernonia oil to amine at varied temperatures to give the corresponding vernolamides. The expected vernolamide from the reaction of 2aminopyridine and the oil was not formed. N-(2-pyridinylmethyl)vernolamide and N-(2pyridinylethyl)vernolamide .exhibited antibacterial activity that was shown to be higher against gram-positive (Bacillus subtiIis) than gram-negative (Escherichia colt) bacteria. The vernolamides did not show any antifungal activity.